"have a complex structure" is a perfectly correct and usable phrase in written English.
You can use this phrase when referring to something that has many interconnected parts or is difficult to comprehend. For example, you could say, "The legal regulations governing international trade have a complex structure."
Her recent work tends to have a complex structure and an unpolished exterior, often placing two separate dances onstage simultaneously.
There is no question that any so-called systemically important financial institution, or SIFI, would have a complex structure and many subsidiaries in foreign jurisdictions.
CHAMP scalar residuals ΔF have a complex structure, especially in the polar caps.
Executing object-oriented programs have a complex structure consisting of numerous objects connected by interobject references.
That is a very complex task and doubtless such a textile will have a complex structure.
Moreover, from Figure 1a, it can be seen that all VIS emission bands have a complex structure.
PP2A has a complex structure, comprising of three subunits: the catalytic (C), regulatory (B) and structural subunit (A).
First, the tax system is complex, containing many different taxes, each often having a complex structure.
Its basin, which receives an annual average precipitation of 27 inches (688 mm), has a complex structure.
It has a complex structure, deals with sometimes brutally unsympathetic characters, and tells the story, both modern and historical, of Haiti, a country that doesn't figure high on most school curricula.
SAC has a complex structure with much of the investing done by people working within affiliates which do not have clear legal ties to Mr Cohen himself.The most important aspect of the charges relates to Mr Cohen's treatment of Mr Martoma.
